Load

Figure 1: Coordination Options - Load

These options control how coordination is handled for single loads.

Option Descriptions
Option Description

Set LTPU to

Select the type of load current calculation to use to set LTPU. The following choices are available:

  • 100% Connected Amps: Amp value for 100% of kVA load.
  • Scaled Connected Amps: Amp value for the scaled kVA of load.
  • Demand Amps: Amp value for the total (kVA * Demand Factor) of load.
  • Code Factor Amps: Amp value calculated using appropriate code factors and demand factors, following a Code (such as NEC).
  • Design Amps: Amp value calculated using appropriate code factors and diversity factor and Design multiplier.

Set STPU to

Select one of the following STPU settings when coordinating with a single load: Min, Medium, or Max.

Set INST to

Select one of the following INST settings when coordinating with a single load: Min, Medium, or Max.

Option Description

Relay Minimum Time Gaps

The time gap between two protective devices is to ensure selective coordination. It is dependent on the combination of devices. The spreadsheet lists different combination of protective devices consisting of induction disk (ID) and solid state (SS) relays, fuses and LV breakers. The minimum time gap is sum of the Overtravel, Safety Margin, auxiliary and breaker opening time.

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